1. Field of the Invention
This invention relates to method and devices for teaching the hitting of tennis balls, and in particular the striking of the tennis ball to impart desired spins and slices thereto.
2. Related Art
U.S. Pat. No. 3,866,912 discloses a target structure mounted on an upright support shaft and a tennis ball simulating structure centrally mounted on the elongated target structure with deflector structures located at each end of the target structure on each opposite side of the tennis ball structure.
The tennis service instructional device of U.S. Pat. No. 3,940,132 reveals a tennis ball releasably held by suction at the mouth of a suspended supple hose at the proper height to be stroked by a tennis racquet such that the tennis ball is released from the restraining force of the suction upon impact by the tennis racquet.
The tennis stroke practice device of U.S. Pat. No. 3,948,517 uses a racquet target and a rotating ball mounted for rotation in a vertical plane upon being struck. A path defining means arrests the rotation of the ball except when it has been hit correctly.
U.S. Pat. No. 3,999,753 discloses a tennis ball dispensing device for practicing tennis strokes that includes an inclined tubular chute for retaining and delivering balls to a flexible sock having an opening therein permitting release of the tennis ball, the sock being suspended from a pivotal ring located at the lower end of the chute.
The tennis stroke practice device comprises a base plate with an upstanding tubular member positioned thereon to receive a z-shaped tube adjustably positioned therein and being comprised of telescoping members for adjusting the length thereof. One of the telescoping portions includes a ball positioned thereon such that the user can place a stringless tennis racquet thereover and practice his stroke by swinging the racquet throughout the length of the z-shaped tube.
U.S. Pat. No. 4,752,070 discloses a racket sport teaching aid device with a frame having a pointing member with a weight attached to the lower end of the frame. The weighted frame plane of the ground at both the back swing and the ball impact point. The pointing member serves as a visual guide which points to the intended target point at completion of the stroke.
Finally, U.S. Pat. No. 4,519,608 reveals a tennis training device comprising a telescopic and orientable rod attachable to a wide belt in the dorsal region of the tennis player and bearing at its end an obstacle, the position of which is adjusted to define the place where the player's racquet is required to come to rest in the correct execution of a stroke of a definite type.